Do Daytime Running Lights Really Make Us Safer?
Jason Lancaster | Sep 03, 2010 | Comments 21
Earlier this week we published instructions on how to disable daytime running lights on a second generation Tundra, and one of the first comments on that post was, Why disable daytime running lights in the first place?
My initial response was “why not?”, but that’s really not much of an answer. So, I did a little digging into the safety benefits of daytime running lights. Here’s what I found:
1. Daytime running lights aren’t required in the USA, but they’re quite popular in Europe and Canada. Canada, Denmark, Finland, Hungary, Iceland, Norway, and Sweden all legally require vehicles to have daytime running lights. In the US, GM made daytime running lights a standard safety feature starting in 1999, and a lot of other manufacturers (Lexus, Mercedes, Saab, Subaru, Volvo, VW, etc.) have done so as well.
2. Multiple studies indicate daytime running lights work. According to a series of studies conducted in Norway, Denmark, and Canada, daytime running lights:
- Reduced daytime crashes between 6-11%
- Reduced left-hand turn crashes by 34%-37%
- Reduced crashes involving pedestrians by 28%
- When crashes did occur, the severity of the crashes was lower on vehicles with daytime running lights (slower speeds)
3. Despite study results, there are many doubters. While multiple studies conducted by governments and private entities around the world seem to indicate that daytime running lights are a safety feature, there are critics of daytime running lights who say:
- Many of the studies that found daytime running lights offered a significant safety benefit were conducted in Canada, Norway, and Denmark, where light levels are different compared to the rest of Europe and North America.
- Many of the studies used relatively small samples.
- Many of the studies were conducted as other safety features were added. Anti-lock braking systems, for example, were being added to vehicles at the same time that daytime running lights where being tested.
4. NHTSA’s most recent study finds no significant benefit to daytime running lights. It’s a little hard to track down, but NHTSA technical report HS 811 029 (pdf) states:
This is the third statistical analysis conducted by NHTSA to evaluate the effectiveness of daytime running lights (DRLs)…the analysis found that DRLs have no statistically significant overall effects
NHTSA’s study did find that daytime running lights reduced light truck crashes about 5%, but otherwise they had no statistically significant impact on safety.
What Does It All Mean?
So, how can these differences between studies be explained? The NHTSA report explains that many of the older studies used a less reliable statistical model (simple odds) rather than a more statistically robust “ratio of odds” method. The NHTSA study also mentions that the definition of “daytime” may differ between studies. If we try to apply a little common sense here:
- There is no statistical safety benefit to daytime running lights during daylight hours, but there’s no conclusive data about their effectiveness during dawn and dusk.
- While earlier studies have flaws, it must be acknowledged that daytime running lights seemed to be more effective in Northern climates where natural light isn’t as bright.
Anyone else see a pattern here? During low-light conditions, headlights seem to be a good safety feature.
No kidding.
Read more about daytime running lights here:
Filed Under: TundraHeadquarters.com
Personally, I think they are a waste of electricity/power on the battery. I could live without them. About the only time they would help around here is if someone should have their headlights on since dark out and the idiots don’t have their normal lights on. It happens more times than it should so in that instance, daytime running lights are useful and safe
mk – You make a great point – DRLs help people remember. I don’t think they’re bad at all, but I don’t blame anyone for getting rid of them. I think it’s amazing that all of the studies performed prior to the NHTSA study of 2008 used a relatively simple statistical method to derive results…makes me wonder about a lot of other studies too.
I am a police officer and ALWAYS turn my headlights on, no matter what I am driving or when. A car with headlights on is more visible from a greater distance than a car without lights, any time of day. It also does help for the dummies that aren’t smart enough to turn on their headlights at night too…
Mike I agree with you. I am a retired LEO and where I live I also get to see some of our drivers driving at night with no headlights on (accident waiting to happen). I also drive with my headlights on all the time, it makes the vehicle easier to see in any weather and at any time.
Mike – That’s another vote for DRL. I talked to a couple of people on Twitter that advocated them as well, especially about an hour after dawn / hour before dusk.
I think that it’s safe to say DRL are effective in dwindling light, as well as a great “back-up” for people who forget their headlights.
Thanks for commenting.
DRLs are dangerous. The current trend for vehicle manufacturers to try to out-do one another with the fitting of ever more ludicrously and recklessly bright LED lights in the false, misguided, name of safety must stop then be reversed.
They are distracting and disorientating especially at moments, such as at junctions or roundabouts, when you need the clearest, calmest, perception of all that is happening around you.
They make it harder to judge the speed and distance of approaching vehicles. They obscure indicators. They make it harder to see road markings, pedestrians and more important hazards in any given scenario.
In rear view mirrors they are very tiring on the eye and, when you do need look in your mirrors, you need take your attention off the direction of travel for longer to look ‘beyond and around’ the confusing bright light whereas when followed by non-offending vehicles only a quick glance is required to safely assess what it is you are seeing.
Yes, Daylight Running Lights grab your attention but that is no more reason to think they are a safe good idea than it is to think that because heat kills germs you should use a blowtorch to wash your hands!
The increased risk of collision, especially in fast moving congested rush hour traffic is immense. Switch them off, keep them off (and flash those coming towards you with them on to educate them as to the error of their ways!)
I do say I have forgotten to turn my lights on when leaving parking lights with lots of Lighting, But its a habit to turn lights on now, yes even in the day. I’ve seen How lights affect the public, If you are to work near Highways, you’ll see how people do not pay attention to you unless you have a Big RED Flag or some bright light’s in there face. I like that they are standard but do NOT think they should be required. I like the DRL disable and the Any-time fog light modifications.
I actually hate DRLs for one reason – people don’t remember that they also have tail lights. I see so many people driving cluelessly in rain or fog because they have a little light in front and nothing in back. I don’t see them as more visible vs. a car that doesn’t have them on. And I also see no benefit especially because I’m a motorcycle rider and people still have yet to pay attention when our full headlight AND tails run once that ignition is flipped.
Andrew – I think you raise some valid concerns as well, especially about increasingly bright headlights. I happen to agree that HID headlamps can be distracting, especially if they’re out of adjustment.
I also like your point about rearview mirrors and DRL…if you have an autodimming rearview, it can get too dark and be hard to use.
I think your point about obscuring indicators is good too.
I’m going back and forth – I think that headlights are needed an hour before dusk and an hour after dawn, as well as during low-light days. Maybe the solution is an electronic eye that’s smart enough to turn lights on when they’re needed and leave them off when they’re not.
Cater – I’m with you – manufacturers can make them an option and/or make it easy for us to disable them.
TXTee – Good point! Leaving them on only works for the front of the vehicle…and your point about motorcycles is good too. One of the arguments against DRLs is that they make it even harder for motorcycle riders to be acknowledged.
Jason – that eye-dea makes complete sense to have an eye that will also work the tails. But isn’t that what automatic headlights already are supposed to do?
TXTee – Yes, I think so…but a lot of people turn automatic headlights off.
Automatic headlights, certainly on UK/European cars, are set to come on too early and skip the all-important ‘sidelight’ phase at dawn and dusk when full blown headlights are disprotionate and actually more glaring than they are during the day or at night proper.
Andrew – Interesting point – never considered that the intensity of headlights that is appropriate for night-time is too bright for dawn/dusk.
There are a lot of wrinkles to this particular issue.
Drls should be selectable. What toyota has failed to remember is the 4x4s are used much by ranchers who traverse miles on private land and spend hours every day working out of the truck. Ranchers are on the go before daylight and after dark. DRLs hamper your ability to see in low light situations by lighting the area immediatly around you and disabling your visability at distances. drls also announce your presence which can be detrimental. Then there is the everpresent security issue of you being seen by tresspassers,thieves and rustlers (yes it is alive and well).
Toyota has gone city and not badmouthing that but we have a totally different set of real NEEDS and toyota has opted to ignore them. Back to Fords or something else!
Ranching 4 Life – I think you make a good point – there should be a process that individual owners can use to disable DRLs on their vehicle that doesn’t involve a tedious process after vehicle start and/or a bunch of mechanical work.
As for Toyota going “city”, I think there’s some validity to that too. Toyota tries to make one truck for everyone, where Ford and GM (and Ram, to a lesser extent) are willing and able to add and subtract features very specifically. In fact, this is part of the reason that Ford and GM sell better…they offer more configurations, which is a big benefit to people with special uses such as yourself.
Thanks for commenting.
Please visit u tube weblink to see pix and comments about Daytime running lamps in canada
http://www.youtube.com/watch?v.....38;list=UL
Many of you are concerned about DRL,s while on the highways. There, many forget they have no tail lights showing when they misuse DRL’s for fog and rain “lights on” state laws.
also Ranchers concern for not wanting them is in a ranch working environment and for the various Law enforcement environments. You do not want your DRLs telling the world you are there. You need to be able to turn them on or off as needed.
[…] press release, the 2013 model will feature “standard Display Audio (6.1 inch screen) and Daytime Running Lights on all models.” Also announced, the 2013 Tacoma Double-Cab 4×4’s with automatic […]
A study back in the 1940s showed having your lights on with the sun behind you can cause your car to be obscured.
The evidence is in that daytime running lights have been proven to increase safety levels. If the sole issue is whether having lights on in the daytime improve safety then the answer is clearly yes.
Right now I am sitting on the beach and have my truck running with my camper plugged into the inverter I installed in the truck so that my daughter can watch a movie with her cousin. All is fantastic except for these bright ad hell running lights, making my campsite glow! That’s why you would shut them off! Because it should be my choice if I want my lights on! Rediculous!